Intraluminal Filling Defects of the Bile Ducts: Differentiation of Stones from Tumors-the Value of Magnetic Resonance Cholangiography in Conjunction with a 3D Spoiled Gradient Echo Gadolinium Enhanced Dynamic Sequence

ABSTRACT

PURPOSE: We wanted to determinate the value of a dynamic volumetric interpolated breath-hold examination (VIBE) as a supplement to MR cholangiography for differentiating biliary stones from tumors when patient are suspected of having intraluminal filling defects on direct cholangiography. MATERIALS AND METHODS: A retrospective analysis was performed for 49 patients who underwent MRI among all the patients who showed intraluminal filling defects on direct cholangiography for evaluating the cause of their jaundice from June 2002 to June 2003. After dividing these patients into two groups, i.e., the group with stones and the group with tumors, we analyzed and compared each MR patterns of 1) signal intensity, 2) shape, and 3) enhancement. RESULTS: High signal intensity on T1-weighted images (p< 0.001, chi-square test), dark signal intensity on T2-weighted images (p< 0.01, Fisher's exact test) or smooth contour of intraluminal filling defects (p< 0.001, chi-square test) could be significantly suggestive findings of stone rather than a tumor mass. Dynamic VIBE is the most specific sequence for differentiating non-enhancing stone from an enhancing mass (p< 0.001, Fisher's exact test). CONCLUSION: We showed that MR cholangiography, when added to the dynamic VIBE sequences, could be an important imaging technique for patients who are suspected of having intraluminal filling defects on direct cholangiography to differentiate stones from tumors. Especially, the addition of dynamic VIBE images can provide the increased level of confidence in the diagnosis.